Since antibiotics were first discovered they’ve saved millions of lives, particularly children. Over time, their excessive use has caused side effects that have made them less and less effective.
Let’s start with some history. Many people know about penicillin and Sir Alexander Fleming, who in 1928, almost by chance discovered that a mold had bactericidal properties, and for this reason, together with two other scholars, he was honored with the Nobel Prize in 1945.
Many years earlier, at the end of the 19th century, an Italian: Vincenzo Tiberio, a military doctor, had observed that in the courtyard from the house where he lived, there was a well from which the family supplied themselves with drinking water. The humidity caused mold to form in the well, and when the mold was removed, those who drank the water developed Enteritis, which did not happen when mold was present. Having a laboratory at his disposal, he submitted this observation to experimental verification, proving the bactericidal effect of mold well before Fleming. Unfortunately, his studies were not sufficiently developed, and we know how the story ended. One could almost say that it was a missed Nobel prize for Italy.
Reviewing a bit of history allows us to understand that antibiotics have been in use for a very long time, and thanks to their use, the infant mortality rate from bacterial infections in the pre-antibiotic era was drastically reduced by 25%. Children died from typhus, pneumonia, tuberculosis and many other bacterial infectious diseases that are much less scary today.
Another important scholar, Paul Erlich, called the antibiotic a “magic bullet”. By this definition, Erlich meant that the antibiotic was capable of targeting pathogenic bacteria, but not the good bacteria that, under normal conditions, reside within our bodies. Unfortunately, science has shown that this is not the case. In fact, if it’s true that antibiotics are only able to affect bacteria and not cells in our body, it’s called selective toxicity. Unfortunately, they don’t distinguish between pathogenic bacteria and good bacteria.
What happens when we take antibiotics?
There are basically two effects. Firstly, the antibiotic affects all bacteria it encounters in its path, whether they are pathogenic or not. The non-pathogenic bacteria constitute the “bacterial flora” resident in our body or even called a microbiota. The microbiota is made up of a very large number of bacterial species that co-exist in balance with each other, while performing beneficial functions for our body. For example, they allow us to digest and metabolize certain foods. Therefore, after a cycle of antibiotics, our bacterial flora is strongly compromised, and for this reason, we feel weaker and we’re more likely to get sick again.
The second effect is the ability of each antibiotic to induce bacterial resistance. Even Fleming, in his speech during the Nobel Prize award ceremony, has since then assumed that if penicillin were to be used incorrectly, there would be a risk of losing its effectiveness. This has happened. In fact, at the time of the introduction of penicillin, 90% of Staphylococci were susceptible to the antibiotic; today, almost all of these bacteria are resistant to penicillin.
How does resistance to antibiotics develop?
It can develop in either a natural or an acquired way. Natural resistance is very rare; in fact, it’s due to the natural inability of some antibiotics to be effective on particular bacteria. The typical example is that of Mycoplasma, on which Penicillins and Cephalosporins are not effective, but fortunately other classes of antibiotics are.
The acquired resistances, are constantly increasing and are borne by bacterial species initially sensitive to a certain antibiotic. With the passage of time and the use of the antibiotic, Nature applies the simple and always effective method of Natural Selection (described by Charles Darwin in the mid-nineteenth century); i.e. the antibiotic-sensitive forms disappear and give way to non-sensitive ones that therefore have less competition for food and “living” space.
Why is bacteria’s resistance to antibiotics considered dangerous?
Because soon, and in some cases, it’s already happening. We will no longer have effective antibiotics, and therefore we’ll be exposed to infections. We know that many bacterial infections are cured, thanks to our immune defenses; otherwise, the human species would already have been extinct for a long time. However, we must also remember that without antibiotics, many children, whose immune systems are not yet fully developed, the elderly, the immunodepressed and all those whose immune system is compromised, would be at great risk.
What can be done to counter the phenomenon of bacterial resistance to antibiotics?
A few clear suggestions:
– Become aware of this dangerous phenomenon and its consequences
– Take antibiotics only with a prescription
– Remember that our organism is the result of an evolution and selection of millions of years, and that it has developed the immune system that has precisely the function of protecting us from external infections
This post is also available in: Italiano